Research on halfway houses for alcoholics has not kept pace with their rise, growth, and spread. This study seeks to fill the gap in current knowledge about the culture and social organization of halfway houses, their typical clients, their characteristic career patterns, and the kinds of treatment outcomes they produce. Two major hypotheses guide the investigation: a) each house produced its own collective produce, a mix of house type, typical client, and characteristic career pattern; b) each house may be rank-ordered according to its proportion of successful treatment outcomes in a given year by halfway house type. The number of positive treatment outcomes discovered at follow-up will be directly proportional to the age of the halfway house. To test these hypotheses, four halfway houses in the Boston area will be studied by a variety of methods, including participant-observation, informal interviewing, questionnaires, and analysis of case records. Each house exemplifies a given organizational type. Predictions have been made for each house as to its modal career pattern and modal client and proportion of positive treatment outcomes it will contribute at follow-up. A random sample of house residents in the year preceding the study will be drawn as a follow-up sample. Interviews with these ex-residents and persons who know them intimately will provide data on their post-treatment status. In addition, records in three existing data bases will be scanned for measures of pre-treatment and post-treatment behavior.